The invention relates to a method to produce moulds or cores, in particular for foundry purposes, from a mixture of sand or moulding material and a binder, which is particularly water soluble and/or hydroscopic, with the mixture being shot in a shooting process into a molding or core tool by at least one shooting unit through at least one discharge opening arranged at a shooting plate and subsequently hardened, and with the area of the discharge opening being moistened and/or kept moist at least via a liquid or water between two shooting processes.
The invention further relates to a device to produce moulds or cores, in particular for foundry purposes, made from a mixture of sand or a moulding material and a preferably inorganic binder, which is preferably water soluble and/or hydroscopic, having at least one discharge opening and a shooting unit provided with a shooting head, with a shooting plate with at least one discharge opening being provided at the shooting head and a device its fastened to, particularly to perform the above-mentioned method.
A method and a similar device are known from DE 103 40 491 B3. Here, a method is provided for carrying this out such that the moisture is fed in form of a finely distributed and/or sprayed or atomized liquid. However, it has shown that here too much liquid can enter the area of the shooting openings or discharge openings and can dissolve the binder out of the mixture of sand or binder or wash it out and/or can render the mixture of sand and binder, which is located in and/or slightly above the shooting openings or discharge openings, too moist so that within the moulding or core tool differently moist mixture areas of sand or molding material and binder can be present, leading to irregularities of the mould or the core.
From DE 101 44 193 C1 it is known to make a moisture carrier contact the filling elements to create a moist atmosphere during the injection molding, which for example may be an absorbent material saturated with a liquid or water. Thereby the shooting opening and the mixture of sand and binder also becomes too wet, which can lead to irregularities in the mixture.
Further, DE 101 44 193 C1 discloses that the moisture supplied shall act as a condensate, which in turn in the area of the shooting opening or discharge opening of a filling element can largely lead to a dilution of the mixture of sand and binder with the above-mentioned disadvantages.